# Django 2.0.dev20170216164632 documentation

# The form rendering API

In older versions, widgets are rendered using Python. All APIs described in this document are new.

Django’s form widgets are rendered using Django’s template engines system.

The form rendering process can be customized at several levels:

- Widgets can specify custom template names.
- Forms and widgets can specify custom renderer classes.
- A widget’s template can be overridden by a project. (Reusable applications typically shouldn’t override built-in templates because they might conflict with a project’s custom templates.)

## The low-level render API

The rendering of form templates is controlled by a customizable renderer class. A custom renderer can be specified by updating the `FORM_RENDERER` setting. It defaults to `'``django.forms.renderers.DjangoTemplates``'`.

You can also provide a custom renderer by setting the `Form.default_renderer` attribute or by using the `renderer` argument of `Widget.render()`.

Use one of the built-in template form renderers or implement your own. Custom renderers must implement a `render(template_name, context, request=None)` method. It should return a rendered templates (as a string) or raise `TemplateDoesNotExist`.

## Built-in-template form renderers

### `DjangoTemplates`

class `DjangoTemplates`

This renderer uses a standalone `DjangoTemplates` engine (unconnected to what you might have configured in the `TEMPLATES` setting). It loads templates first from the built-in form templates directory in `django/forms/templates` and then from the installed apps’ templates directories using the `app_directories` loader.

If you want to render templates with customizations from your `TEMPLATES` setting, such as context processors for example, use the `TemplatesSetting` renderer.

### `Jinja2`

class `Jinja2`

This renderer is the same as the `DjangoTemplates` renderer except that it uses a `Jinja2` backend. Templates for the built-in widgets are located in `django/forms/jinja2` and installed apps can provide templates in a `jinja2` directory.

To use this backend, all the widgets in your project and its third-party apps must have Jinja2 templates. Unless you provide your own Jinja2 templates for widgets that don’t have any, you can’t use this renderer. For example, `django.contrib.admin` doesn’t include Jinja2 templates for its widgets due to their usage of Django template tags.

### `TemplatesSetting`

class `TemplatesSetting`

This renderer gives you complete control of how widget templates are sourced. It uses `get_template()` to find widget templates based on what’s configured in the `TEMPLATES` setting.

Using this renderer along with the built-in widget templates requires either:

1. `'django.forms'` in `INSTALLED_APPS` and at least one engine with `APP_DIRS=True`.
2. Adding the built-in widgets templates directory (`django/forms/templates` or `django/forms/jinja2`) in `DIRS` of one of your template engines.

Using this renderer requires you to make sure the form templates your project needs can be located.

## Context available in widget templates

Widget templates receive a context from `Widget.get_context()`. By default, widgets receive a single value in the context, `widget`. This is a dictionary that contains values like:

- `name`
- `value`
- `attrs`
- `is_hidden`
- `template_name`

Some widgets add further information to the context. For instance, all widgets that subclass `Input` defines `widget['type']` and `MultiWidget` defines `widget['subwidgets']` for looping purposes.

## Overriding built-in widget templates

Each widget has a `template_name` attribute with a value such as `input.html`. Built-in widget templates are stored in the `django/forms/widgets` path. You can provide a custom template for `input.html` by defining `django/forms/widgets/input.html`, for example. See Built-in widgets for the name of each widget’s template.

If you use the `TemplatesSetting` renderer, overriding widget templates works the same as overriding any other template in your project. You can’t override built-in widget templates using the other built-in renderers.